1. Field of the Invention
This invention relates generally to device fabrication, and more particularly to apparatus and methods for magnetron sputtering.
2. Description of the Background Art
In a physical vapor deposition (xe2x80x9cPVDxe2x80x9d) process, atoms sputtered from a target are deposited onto a substrate. The target, which could be made of aluminum or copper, for example, is located a distance away from the substrate. A plasma of a gas suitable for sputtering, such as argon, is maintained between the target and the substrate. Ions of the sputtering gas are accelerated onto the target. When accelerated ions hit the target, atoms are sputtered from the target and onto the substrate. The use of magnetic fields to enhance a PVD process is also known as magnetron sputtering.
In any PVD process, it is desirable to achieve good deposition uniformity both at feature level and across the substrate. It is also important to have high deposition rates in order to maximize the number of substrates that can be processed within a certain period of time. Ideally, a magnetron apparatus capable of providing good deposition uniformity at high deposition rates should also have a relatively low cost of ownership.
The present invention relates to a novel magnetron apparatus. In one embodiment, a magnetron apparatus includes an essentially flat target having a low height-to-width ratio. The essentially flat target may be planar, dish-shaped, or stepped-shape, for example. A main magnet is located behind the flat target to provide main magnetic fields. Magnets located near the target and underneath a substrate may be configured to maintain a high density plasma and to control the flow of plasma onto the substrate.